[No.1]

Ok so I've been having issues with my damping module under the right front seat and today has got me stumped. I was out poking and proding around checking power and grounds. Referenced the wiring diagrams I have and found the power wires location on the CJB so the start button in the "on" position I was getting no voltage reading on the blue and brown wire at either end, so I started the car and checked but still reading no Volts
So I shut the car off and unplugged the power from the module and probed the connector slot for the power wire and not great but I was getting 7.6ish volts now so I thought maybe I was making contact when it was attached and that's why the reading of no volts so I checked the other end coming from the CJB and got the same 7.6ish (should it not be battery voltage?). Started the car and at both ends got slightly over 9V
This is the fun part I had both Meter ends still attached to a ground on vehicle and power wire coming from CJB when I shut car off the volts dropped back down which I expected but what I didn't expect was as soon as the harness is attached to the CVD module the volts go right to zero. At first I was like no no no that's not what the f____ . So I have power through the wire unplugged but hooked up I have none?? What does that mean?
Anybody that can provide some help or insight would be greatly appreciated because all I have at this point is guesses and with these cars u don't go by guesses
"Know what you know and know what you don't know"
Thank you in advance

 

[Beevee]

It ‘sounds’ like a dead short to ground when you plug it in

 

[Phil1]

Yep, sounds like a dead short on the output side of the module.

Often one of the first things we have at work when dealing with "dead" PLCs is that we will unplug all the inputs and outputs and run the PLC with power alone, they almost always come back to life miraculously. Then we just plug each bank of inputs and outputs back in to narrow down the fault. Almost always a cabling issue or a knackered proximity sensor something along those lines.

With this you say the damping module.... Is this for the suspension? I'd start simple and disconnect all the plugs from the top of the struts for a start and work from there.

 

[No.1]

Yep, sounds like a dead short on the output side of the module.

Often one of the first things we have at work when dealing with "dead" PLCs is that we will unplug all the inputs and outputs and run the PLC with power alone, they almost always come back to life miraculously. Then we just plug each bank of inputs and outputs back in to narrow down the fault. Almost always a cabling issue or a knackered proximity sensor something along those lines.

With this you say the damping module.... Is this for the suspension? I'd start simple and disconnect all the plugs from the top of the struts for a start and work from there.

Thank you for the advice and yes it's suspension control module B (continuos vehicle damping or adaptive damping module) it looks like I know what my afternoon will entail, checking all 4 strut sensors and all 4 height sensors. When the system is fixed and there is no more shorts to power or ground should I be seeing battery voltage at the module? I can't find any literature on its functioning voltage, right now I can only guess

 

[Gav]

have you downloaded/consulted the workshop manual from here?

 

[FCS]

When you see volts drop or go away when connecting a load, assuming fuses are not blowing and or things are getting hot. It usually is a high resistance feed. Which is often a bad connection from the source of the volts ie, module.
A bit like trying to start a car with a 10 amp/Hr battery.
I assume you checked the load for low resistance, short etc.

 

[Beevee]

Plug them in one at a time, when you get to the one that’s the failure, check the wiring and load for shorts to ground
If it’s the wiring, you can fix it. If it’s the load, maybe unfixable

 

[No.1]

Based on all your extremely helpful advice and the reading I've done. I just have one question before I start tearing the car apart to test sensors and grounds. Currently my CJB is corrupt and that is the source for the load so would the nackered CJB be the reason for the volt drop when connected?
Sorry I lied I have another question
In order to reprogram the CJB do I need communication from all modules or can I do the CJB work and then check back to see if this damping module issue is resolved?
Thank you again gentleman for the help

 

[FCS]

The answer to your first question is quite possibly. The second question is that any faulty module on the CAN bus (fast or medium) can throw the lot. We have experts on here for CJB they may kick in to help.

 

[Beevee]

Have you heard of the water wicking issue which is a fault with the windscreen washer pump?
Water from the bottle travels through the pump, up the wiring and into the cjb - which can wreck it! - very expensive
Check the plugs in the cjb for corrosion and water. Clean if possible
This could be the source of your short…
As for the reprogramming, I would imagine you would need to communicate with some of the modules, i.e. for the security ( door module, dash, dunno what else) so that they all recognise each other

 

[No.1]

It has been a long evening and night for me. I have the passenger side of my car tore out for access to the module, trunk lining is in my living room now(wife loves that) lol I gotta say all this spider web of wiring back here is WOW!!!

I would hate to see what behind the dash looks like. So to finish off the day I fired up SDD and ran a few service functions to determine the state of my CAN lines and despite a couple modules displaying question marks on the main screen, SDD was still able to talk to them all so I puckered me arsehole and I configured CJB as new ( one of the top 5 most stressful times in my life). Almost everything went according to plan, I can't quite wrap my head around it but since the first disconnect and frying the CJB whenever it came to the keys, it was always the same key that kept causing me issues when it came to programming them back to the car. Key 1 locks/unlocks and arms/disarms alarm, they both work to start the car but key 2 just won't fully pair and so it's only function is its able to start the car (maybe the transponder or something got fried on the motherboard) other than that it was successful and tomorrow I go back in to see if that has corrected any of the issues.
I have came across alot of literature on the wash pump wicking into the CJB and the sunroof seal leaking and causing water ingress issues to the CJB as well all harnesses and pins are corrosion free thank goodness. These cars are just full of surprises aren't they

 

[Beevee]

You’ve been mega busy!
I’ve never seen them stripped to that extent - I hope it all goes back together ok!
As for your key, the transponder is working fine if the car starts
All it’s for is to start the car and open the doors (the car’s security stuff)
And just for info, it’s not powered by the keyfob battery despite what other folk say, it works via induced voltages by signals from the car

 

[No.1]

You’ve been mega busy!
I’ve never seen them stripped to that extent - I hope it all goes back together ok!
As for your key, the transponder is working fine if the car starts
All it’s for is to start the car and open the doors (the car’s security stuff)
And just for info, it’s not powered by the keyfob battery despite what other folk say, it works via induced voltages by signals from the car

That's interesting bit of info and have never heard that before. What's the point of the fob battery and how do some get the low smart key battery message?
So if only the one key keeps failing the security function part but the other key functions for both parts of the system
Am I missing something or doing something wrong?

 

[No.1]

Can anyone assist me with finding out where this wire location is I'm having a heck of a time finding it (highlighted in yellow) and what does the CSA (in red) mean?
Thank you gentleman

 

[Horlicks]

CSA is cross sectional area. Can't help with the yellow/green wire though.

 

[Horlicks]

Looks like it is the supply wire for the accelerometers. If you have the wiring diagrams just search for spl872.

 

[Gav]

That's interesting bit of info and have never heard that before. What's the point of the fob battery and how do some get the low smart key battery message?
So if only the one key keeps failing the security function part but the other key functions for both parts of the system
Am I missing something or doing something wrong?

The battery is needed to transmit the code to the car.

 

[Beevee]

That's interesting bit of info and have never heard that before. What's the point of the fob battery and how do some get the low smart key battery message?
So if only the one key keeps failing the security function part but the other key functions for both parts of the system
Am I missing something or doing something wrong?

The battery is there to power the pcb (the buttons)
The transponder is totally separate and unconnected and can look like a wee square bit of plastic or a capsule type thing, so when you get the fob battery low message, it’s just telling you that the buttons might stop working.

 

[Horlicks]

Then why with the older cars did they have the niche for placing the key in to start the car if the battery was dead?

 

[Beevee]

Then why with the older cars did they have the niche for placing the key in to start the car if the battery was dead?

Dunno…
Tidiness?
Dated/cheaper electronic bits?